Petrous apex meningiomas: an alternative surgical approach

The literature describes a variety of surgical approaches to deal with meningiomas that involve the apex of the petrous bone and lie predominantly in the posterior fossa, e.g. the transpetrosal (translabyrinthine and transcochlear), the combined supra- and infratentorial, the subtemporal with or without pyramid resection, the suboccipital and the orbitozygomatic approaches. This study presents an alternative surgical approach, namely a modification of the occipital craniotomy with or without tentorial division. This approach was used for the removal of three petrous bone apex meningiomas which were medium to large in size and located predominantly in the posterior fossa with extension into the middle fossa. Complete tumour excision was achieved with no morbidity and no mortality.     

Endolymphatic sac carcinoma of the right petrous bone in Von Hippel-Lindau disease.

A large endolymphatic sac papillary adenocarcinoma in a patient with Von Hippel-Lindau (vHL) disease is reported. A 31-year-old man was treated for a left eye retinal angioma 10 years previously and had been blind in that eye since. He was admitted with progressive tinnitus, lower cranial nerve paresis and ataxia. Investigations revealed a vascular and bone-eroding petrous tumour. The entirely extradural tumour involved a large part of the petrous bone and extended into the cerebellopontine angle. The vascular tumour was radically resected using a presigmoid approach after feeding vessel embolisation. The literature on this rare clinical entity is briefly discussed.     

经扩大乙状窦后入路手术切除大型岩骨后脑膜瘤

目的 探讨经扩大乙状窦后入路切除大型岩骨后脑膜瘤的手术方法和治疗效果.方法 应用扩大乙状窦后入路切除16例大型岩骨后脑膜瘤,肿瘤最大径均超过4 cm,有4例肿瘤侵入岩骨,术中完全暴露横窦和乙状窦,与硬脑膜一并分别向上方和前方牵开,充分暴露小脑幕下方和岩骨背面.结果 本组肿瘤全切除15例,次全切除1例,无手术死亡,15例患者术前症状消失或改善,术后永久性面瘫1例,脑脊液漏1例.随访3个月-5年,随访期间复查MRI未见肿瘤复发.结论 经扩大乙状窦后入路切除大型岩骨后脑膜瘤具有能够早期处理肿瘤基底、有效控制术中出血、明显扩大手术暴露和提高肿瘤全切率等优点.     

Total removal of huge chondrosarcoma of the skull base with facial nerve resection and reconstruction

Chondrosarcomas of the skull base are locally aggressive tumours, and radical surgical resection is often difficult because of involvement of important neural structures in the skull base. We report the successful total resection of a huge skull base chondrosarcoma extending both intra- and extracranially. The tumour involved the left mastoid process, entire petrous bone, jugular foramen, posterior fossa and the parapharyngeal space. Since the facial nerve in the fallopian canal was totally involved by the tumour, the nerve was sacrificed and reconstructed using a great auricular nerve graft. The removal of the tumour was radical and complete. The functional recovery of the reconstructed facial nerve was excellent. The patient has almost fully recovered from the other neurological symptoms and has been free of tumour recurrence for 4 years after surgery.     

Cranial fasciitis located at the temporal region in a 2-year-old girl

Introduction

Cranial fasciitis is an exceedingly rare, benign, fibroblastic tumour of the skull of young children. It was first described in 1980 by Lauer and Enzinger as a subset of nodular fasciitis. There are fewer than 55 cases described in the literature.

Case report

We describe the presentation of a 2-year-old girl with a rapidly growing left temporal lesion, initially treated as an intramuscular haemangioma with propanolol. Following failure of response to this management, radiological and histological investigations indicated cranial fasciitis, and multidisciplinary surgery was undertaken via a bicoronal incision. Gross total resection was carried out, and the lesion was found to be adherent to but not infiltrating the dura. The petrous bone and zygomatic arch appeared destroyed, leaving a large temporal bony defect. This was repaired with a split calvarial graft from the outer table of the right parietal bone.

Discussion

Histology confirmed a diagnosis of cranial fasciitis. She had an uneventful post-operative course and was discharged home well. A CT scan 8 months post-operatively showed no residual lesion and it was noted that the reconstruction had fully integrated and the zygomatic arch had reformed.     

An endolymphatic sac tumor with imaging features of aneurysmal bone cysts: differential diagnostic considerations

Background

Endolymphatic sac tumors (ELSTs) are rare, slow-growing tumors of the petrous bone. Despite the typical localisation, their radiological diagnosis can be challenging due to the variety of other tumors potentially showing similar features.

Case report

We present a 16-year-old child with progressive hearing loss, vertigo, and tinnitus who had a large petrous bone lesion showing imaging features of both ELSTs and aneurysmal bone cysts (ABCs). The patient underwent preoperative embolization of the tumor-supplying vessels and subsequently a subtotal resection. Histological examination revealed an ELST.

Conclusion

Despite the rarity of petrous bone ABCs, they should be considered as a differential diagnostic alternative of ELSTs due to their similar imaging appearance.     

Delayed otogenic pneumocephalus complicating ventriculoperitoneal shunt

Tension pneumocephalus complicating ventriculoperitoneal shunt is extremely rare. We report an elderly male who developed delayed tension pneumocephalus 12 months after ventriculoperitoneal shunt for hydrocephalus complicating aneurysmal subarachnoid hemorrhage. Fine-cut reformatted computer tomography scan revealed a large pneumatocele on the petrous apex associated with tegmen tympani defect. The shunt valve pressure was temporarily raised from 120 mm H 2 O to 200 mm H 2 O, and the patient underwent successful subtemporal extradural repair of the bony defect in the temporal bone. Although extremely rare, otogenic tension pneumocephalus is a potentially life-threatening condition, and urgent surgical repair of the bony defect in the temporal bone reduces the risk of both the morbidity and mortality.     

Piezosurgery for safe and efficient petrous bone cutting in cerebellopontine angle and petroclival meningioma surgery

Intradural petrous bone drilling has become a widespread practice, providing extended exposure in the removal of cerebellopontine angle (CPA) or petroclival tumors. Adjacent neurovascular structures are at risk, however, when drilling is performed in this deep and narrow area. Hence, this study evaluates the use of Piezosurgery (PS) as a non-rotating tool for selective bone cutting in CPA surgery.A Piezosurgery® device was used in 36 patients who underwent microsurgery for extra-axial CPA or petroclival tumors in our Neurosurgical Department between 2013 and 2019. The clinical and radiological data were retrospectively analyzed. The use of PS was evaluated with respect to the intraoperative applicability and limitations as well as efficacy and safety of the procedure.Piezosurgical petrous bone cutting was successfully performed in the removal of meningiomas or extra-axial metastases arising from the dura of the petroclival region (21 patients) or petrous bone (15 patients). PS proved to be very helpful in the deep and narrow CPA region, considerably reducing the surgeon’s distress toward bone removal in close proximity to cranial nerves and vessels in comparison to common rotating drills. The use of PS was safe without injuries to neurovascular structures. Gross total resection was achieved in 67% of petroclival and 100% of petrous bone tumors.Piezosurgery proved to be an effective and safe method for selective petrous bone cutting in CPA surgery avoiding rotating power and associated risks. This technique can particularly be recommended for bone cutting in close vicinity to critical neurovascular structures.     

Reconstruction of the facial nerve in acoustic neurinoma surgery. juxtapontine–intratemporal nerve graft

Five cases of large acoustic neurinomas (diameter 2.5 cm) with involvement of the facial nerve in the tumour capsule are presented. The preoperative function of the facial nerve was normal. During surgery, in order to achieve a radical tumour removal, the facial nerve was severed juxtapontine. Reconstruction was performed at the same procedure using a 5-6 cm long sural nerve graft. Thus the central juxtapontine stump was joined to the peripheral stump in the facial nerve canal of the petrous bone. After six months, all five patients exhibited a well functioning mimic and a good eyelid function. At the one year control four patients had normal nerve function clinically and one patient still showed asymmetrical mimic.     

Intracranial aneurysmal bone cyst manifesting as a cerebellar mass

A 17-year-old boy presented with symptoms of raised intracranial pressure for a month. Investigations revealed a large extra-cerebellar mass. The lesion was radically resected. It arose from the petrous bone. Histology revealed that the lesion was an aneurysmal bone cyst [ABC].     

Surgical management of posterior petrous meningiomas

Background and purposeThe aim of the study is to present our experience in the surgical treatment of posterior petrous meningiomas in regard to clinical presentation, surgical anatomy, complications and long-term functional postoperative results.Material and methodsA series of 48 consecutive patients operated on for posterior petrous meningiomas at the authors’ institution between 2002 and 2011 is reported. The main symptom on first admission was hypoacusis, impairment of the fifth cranial nerve and cerebellar ataxia. The tumour was found to be attached to the premeatal dura in 46%, the inframeatal dura in 29% and the postmeatal dura in 25% of cases. Tumour resection was categorized as grade I in 16 patients, grade II in 29 patients, grade III in 1 patient and grade IV in 2 patients, according to the Simpson classification system. The petrosal approach and retrosigmoid approach were suitable for posterior petrous meningiomas.ResultsPostoperative facial nerve dysfunction appeared in 8 and further deteriorated in 2 patients. Hearing function deteriorated after surgery in 8 and improved in 2 cases. Perioperative death occurred in two patients. Tumour recurrence was observed in two patients, and both underwent a second operation and postoperative stereotactic radiotherapy.ConclusionsSurgical treatment of posterior petrous meningiomas has become increasingly safe but these tumours still remain a surgical challenge because of the relatively high incidence of permanent complications associated with their removal. The site of displacement of the cranial nerves depending on the dural origin of the tumour has the most influence on the related difficulties in its removal.     

经岩骨乙状窦前入路处理岩斜区肿瘤(附40例报告)

目的提高经岩骨乙状窦前入路处理岩斜区肿瘤的手术疗效.方法对采用经岩骨乙状窦前入路处理的40例岩斜区肿瘤病人的临床特征、手术方法、手术结果及术后并发症进行回顾性分析.以岩骨乙状窦交叉点和内淋巴囊裂作为磨除岩骨的定位标志,以减少岩骨内结构的损伤.结果肿瘤全切除27例,次全切除9例,部分切除4例.无手术死亡.术后主要并发症为脑神经损伤、脑组织水肿、肌力减退等.结论经岩骨乙状窦前入路是处理岩斜区肿瘤较好的手术方法.大多可全切除肿瘤.     

经枕下乙状窦后-内听道上结节入路切除岩斜区脑膜瘤

目的探讨采用枕下乙状窦后-内听道上结节入路切除岩斜区脑膜瘤的安全性、有效性,以及优缺点。方法回顾性分析自2002年1月至2004年12月采用枕下乙状窦后-内听道上结节入路切除的岩斜区脑膜瘤11例。所有肿瘤主体均位于后颅窝,侵袭海绵窦和/或Meckel's腔,其中6例伴有脑干受压移位,3例有岩尖骨性改变,5例肿瘤部分或全部包绕椎基底动脉及其主要分支。结果肿瘤全切除8例,次全切除3例。术前有听力者9例,其中1例因肿瘤巨大,术后听力丧失。出院后随访,7例、3例和1例面神经功能分别恢复至1级、2级和3级。所有患者术后恢复满意,无死亡和严重并发症发生。结论枕下乙状窦后-内听道上结节入路是一种安全有用的乙状窦后改良入路,适合于主体在后颅窝,并向中颅窝、Meckel's腔扩展的岩斜区大型肿瘤的手术切除。     

颞下经小脑幕锁孔入路解剖与临床应用

目的通过神经导航下颞下经小脑幕锁孔入路的解剖和手术方案研究,探讨该入路临床应用效果。方法应用成人头颅标本12例(24侧),模拟颞下经小脑幕锁孔入路,观察暴露的岩斜区解剖结构;利用神经导航技术定位标本岩骨内部结构,最大限度磨除岩尖,观察斜坡鞍后区,上、中斜坡区等结构;利用该入路切除11例临床颅底肿瘤,探讨该入路的安全性和实用性。结果颞下经小脑幕锁孔入路可完全暴露鞍旁区,通过海绵窦外侧壁的手术三角可对累及海绵窦内外病变进行直视手术;神经导航辅助下耳蜗、内听道等结构定位准确,头颅标本岩尖磨除后耳蜗内侧缘岩尖剩余最大骨质平均厚度(0.8±0.19)mm,内侧视角较非导航入路增加(8±2.5)°,后外侧视野增加了(25±3.2)°,获得(3.3±0.4)cm2硬膜显露,明显扩大了后颅窝的暴露范围。临床病例资料肿瘤全切除6例,次全切3例,大部分切除2例,手术时间与既往相比缩短1~1.5 h,术后新增脑神经损害症状或原有脑神经损害症状加重3例,无长期昏迷及手术相关死亡病例。结论神经导航辅助下颞下经小脑幕锁孔入路,能最大程度暴露蝶岩斜区病变,有利于提高肿瘤的全切率和术后疗效。     

Fat graft-assisted internal auditory canal closure after retrosigmoid transmeatal resection of acoustic neuroma: Technique for prevention of cerebrospinal fluid leakage

The retrosigmoid transmeatal approach remains an important strategy in the surgical management of acoustic neuromas. Gross total resection of acoustic neuromas requires removal of tumor within the cerebellopontine angle as well as tumor involving the internal auditory canal (IAC). Drilling into the petrous bone of the IAC can expose petrous air cells, which can potentially result in a fistulous tract to the nasopharynx manifesting as cerebrospinal fluid (CSF) rhinorrhea. We describe our method of IAC closure using autologous fat graft and assessed the rates of postoperative CSF leakage. We performed a retrospective study of 24 consecutive patients who underwent retrosigmoid transmeatal resection of acoustic neuroma who underwent our method of fat graft-assisted IAC closure. We assessed rates of postoperative CSF leak (incisional leak, rhinorrhea, or otorrhea), pseudomeningocele formation, and occurrence of meningitis. Twenty-four patients (10 males, 14 females) with a mean age of 47 years (range 18–84) underwent fat graft-assisted IAC closure. No lumbar drains were used postoperatively. There were no instances of postoperative CSF leak (incisional leak, rhinorrhea, or otorrhea), pseudomeningocele formation, or occurrence of meningitis. There were no graft site complications. Our results demonstrate that autologous fat grafts provide a safe and effective method of IAC defect closure to prevent postoperative CSF leakage after acoustic tumor removal via a retrosigmoid transmeatal approach. The surgical technique and operative nuances are described.     

经扩大乙状窦后人路手术切除大型岩斜区脑膜瘤

目的 探讨扩大乙状窦后入路在显微手术切除大型岩斜区脑膜瘤巾的应用.方法 采用扩大乙状窦后入路的手术方式,显微切除人刑岩斜区脑膜瘤6例,肿瘤最大直径3.4～6.7 cm,平均4.5 cm,术中切除枕骨和乳突.完全显露横安和乙状窦,通过悬吊硬脑膜将它们分别向上方和前方牵开,有效地减少了两个粗大的静脉窦对小脑幕下方和岩骨背面的遮挡,手术视野明显增大,能够充分暴露小脑幕和岩骨背面.结果 本组肿瘤全切除3例,次全切除2例.大部切除1例,无手术死亡,神经功能较术前改善3例,与术前相同3例,2例出现新增脑神经损害,未发生脑脊液漏和切口感染.术后随访6-58个月.所有病例MRI复查未见肿瘤复发或增大.结论 扩大乙状窦后入路具有增加暴露范围、扩大手术视角、早期阻断肿瘤血液供应、避免过度牵拉小脑、改善深部结构的显露、有利于保护脑神经和重要血管等优点.     

Analysis of temporal bone thickness outside of the petrous temporal bone between superior semicircular canal dehiscence and normal patients

BackgroundSSCD is a rare inner ear disorder. This study aims to compare the thickness of the temporal bone beyond the petrous portion between healthy subjects and those with SSCD to determine whether the etiopathology of SSCD is localized to the petrous temporal bone or generalized to other parts of the temporal bone.MethodsA retrospective chart review of electronic medical records from September 2011 to February 2018 was conducted at a single-institution study at the University of California, Los Angeles. Participants were divided into two groups: Group 1 had a confirmed diagnosis of SSCD, while Group 2 had no known ear or temporal bone pathology. Participants’ high-resolution coronal and axial temporal bone computed tomography scans were analyzed. Regions within the temporal bone were measured and compared between the two groups.ResultsA total of 262 scans were included. Group 1 consisted of 103 scans, while Group 2 consisted of 159 scans. There was no statistically significant difference in the thickness of temporal bones between patients diagnosed with SSCD and patients without otologic disease.ConclusionThe results suggest that the etiology of SSCD is limited to the petrous portion of the temporal bone. SSCD may be unrelated to a larger process of global temporal bone degeneration. Additional clinical screening for regions outside the petrous temporal bone is not warranted unless SSCD patients present with symptoms characteristic of other temporal bone pathologies.     

颞下小骨窗人路显微手术临床应用

目的改良常规颢下人路,以减少手术创伤达到微创的目的。方法采用耳前1cm颧弓向上向后弧形切口,绕行耳廓上方约1cm到达乳突,铣开4cm×2cm大小骨窗,平中颅底,经颞下行中颅底部位病灶的手术治疗15例。结果9例三叉神经鞘瘤全切除8例,次全切1例。4例岩尖区天幕下脑膜瘤和2例颞底胶质瘤均全切除。结论颞下小骨窗人路可以达到常规颞下入路的效果,可以满足中颅窝后部、颞叶底面及天幕区的肿瘤切除术的要求,是一种行之有效的微创手术人路。     

咽鼓管上三角在扩大经鼻蝶入路神经内镜手术切除岩尖下区肿瘤中的意义

目的 探讨咽鼓管上三角(SET)在扩大经鼻蝶入路神经内镜手术切除岩尖下区肿瘤中的意义。方法 回顾性分析2017年1月至2021年8月扩大经鼻蝶入路神经内镜手术切除的13例岩尖下区肿瘤的临床资料。连接骨性咽鼓管内侧与咽鼓管圆枕顶部的水平线定义为SET,颈内动脉岩骨段水平部和咽鼓管与水平线的倾斜角度分别定义为角α和角β。根据术前MRI增强影像评估肿瘤向两侧扩展程度,分为重度、中度、轻度扩展。结果 术后病理检查显示脊索瘤8例,软骨肉瘤3例,脑膜瘤2例。肿瘤全切除6例(46.2%),次全切除3例,部分切除4例。术后发生脑脊液漏2例、外展神经麻痹2例,未发颈内动脉损伤。术后随访6～36个月,2例复发,再次手术,无死亡病例。定量测量13例26侧SET的面积在28.0～95.2 mm²,平均(65.6±22.2)mm²。8侧重度扩展SET面积[(76.5±27.6)mm²]较10侧中度扩展侧SET面积[(42.2±15.7)mm²]和8侧轻度扩展SET面积[(40.5±10.7)mm²]明显...     

改良部分迷路切除岩骨尖入路的岩骨磨除技术

目的探讨改良部分迷路切除岩骨尖入路(PLPA)的岩骨磨除技术。方法测量10例(20侧)成人干颅骨标本骨性结构间的距离;对15例(30侧)成人尸头采用PLPA及改良PLPA暴露岩斜区,观察岩斜区解剖结构的暴露情况及有无岩骨内重要结构的损伤,测量骨窗大小及增加的视野、视角,对结果进行统计学分析。结果岩浅大神经沟到岩骨嵴的平均距离为12.8m m,D onaldson线到岩骨嵴的平均距离为12.2m m,所有标本均未损伤岩骨段颈内动脉等重要结构。改良PLPA可充分暴露岩斜区。改良PLPA较PLPA骨窗小,差异有高度统计学意义(P<0.01);磨除骨质后两入路增加的手术视野和视角无统计学差异(P>0.05)。结论改良PLPA较PLPA创伤小,暴露同样充分。岩骨磨除操作是改良PLPA的关键技术,不容易损伤岩骨内重要结构,有可能保留听力;D onaldson线可作为磨除岩骨的安全界限。